Commit 5fd6739e authored by Miquel Raynal's avatar Miquel Raynal
Browse files

spi: mxic: Fix the transmit path 



By working with external hardware ECC engines, we figured out that
Under certain circumstances, it is needed for the SPI controller to
check INT_TX_EMPTY and INT_RX_NOT_EMPTY in both receive and transmit
path (not only in the receive path). The delay penalty being
negligible, move this code in the common path.

Fixes: b942d80b ("spi: Add MXIC controller driver")
Cc: stable@vger.kernel.org
Suggested-by: default avatarMason Yang <masonccyang@mxic.com.tw>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: default avatarZhengxun Li <zhengxunli@mxic.com.tw>
Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20220127091808.1043392-10-miquel.raynal@bootlin.com
parent f9d7c726

drivers/spi/spi-mxic.c

+12 −16
Original line number Diff line number Diff line
@@ -304,10 +304,8 @@ static int mxic_spi_data_xfer(struct mxic_spi *mxic, const void *txbuf, 


		writel(data, mxic->regs + TXD(nbytes % 4));



		if (rxbuf) {

		ret = readl_poll_timeout(mxic->regs + INT_STS, sts,

						 sts & INT_TX_EMPTY, 0,

						 USEC_PER_SEC);

					 sts & INT_TX_EMPTY, 0, USEC_PER_SEC);

		if (ret)

			return ret;
@@ -318,11 +316,9 @@ static int mxic_spi_data_xfer(struct mxic_spi *mxic, const void *txbuf, 
			return ret;



		data = readl(mxic->regs + RXD);

		if (rxbuf) {

			data >>= (8 * (4 - nbytes));

			memcpy(rxbuf + pos, &data, nbytes);

			WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);

		} else {

			readl(mxic->regs + RXD);

		}

		WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);